ThommyW Posted August 3, 2009 Share Posted August 3, 2009 Hello GWB Users, since 5 days I am in great trouble with my GWB calculations. Without knowing it, it seems that, despite all Pitzer parameters present, the data bases were titled with activity model = "Debye Huckel" instead of "h-m-w". So every time it worked, it was just because the D H model was used. Finally, thanks to Tom, I found out that the activity model was "debye-huckel" and when I put 'h-m-w' the calculation doesn't work anymore. Instead of the calculation I get a message "bad beta Pitzer pair'. the worst: This is true for any data base ever produced since last year ago... and we added very much data.... The only parameters working were finally those of the file thermo_hmw.dat. So using an input file for 'sea water' (and eliminating SiO2) together with thermo_hmw.dat the calculation works (but is boring). If I add any element of our data base in a small concentration (as I also did for the D - H files) and a small quantity of the pure solid element as reactant, I get another error: "calc_hmw: max charge too large". This is true for any element and any big or small quantity of it. Considering that in the h-m-w file it is written, that the parameters are parsed "word by word and no aligning of parameters is necessary", I don't understand why I get the message "bad pitzer pair". At first we thought of point ('.' ) - Comma (',') - problem, but there are no commas in the numbers. Considering that there is no problem with the data base using the debye huckel model, the problem has to be somewhere in the Pitzer block. In the best case, varying the Eh(V) value and the concentration or reactant quantities I get the following message (the order of magnitude varying slightly) : Ionic strength out of range. Largest residual(s): Resid Resid/Totmol Cbasis -------------------------------------------------------- Cu+ 1.695e+014 1 4.498e-006 -------------------------------------------------------- Finally I found out, that all this trouble only concerns our big data bases (even though working with the D H model). Just starting with thermo_hmw.dat and adding one element (Cu), one redox species (Cu+), some aqueous species and some minerals, the data base works for a saline solution with this one element added and some traces of it as ion. Does anybody know that penomenon ?? Thanks Thomas Willms Quote Link to comment Share on other sites More sharing options...
ThommyW Posted August 11, 2009 Author Share Posted August 11, 2009 Hello GWB Users, since 5 days I am in great trouble with my GWB calculations. Without knowing it, it seems that, despite all Pitzer parameters present, the data bases were titled with activity model = "Debye Huckel" instead of "h-m-w". So every time it worked, it was just because the D H model was used. Finally, thanks to Tom, I found out that the activity model was "debye-huckel" and when I put 'h-m-w' the calculation doesn't work anymore. Instead of the calculation I get a message "bad beta Pitzer pair'. the worst: This is true for any data base ever produced since last year ago... and we added very much data.... The only parameters working were finally those of the file thermo_hmw.dat. So using an input file for 'sea water' (and eliminating SiO2) together with thermo_hmw.dat the calculation works (but is boring). If I add any element of our data base in a small concentration (as I also did for the D - H files) and a small quantity of the pure solid element as reactant, I get another error: "calc_hmw: max charge too large". This is true for any element and any big or small quantity of it. Considering that in the h-m-w file it is written, that the parameters are parsed "word by word and no aligning of parameters is necessary", I don't understand why I get the message "bad pitzer pair". At first we thought of point ('.' ) - Comma (',') - problem, but there are no commas in the numbers. Considering that there is no problem with the data base using the debye huckel model, the problem has to be somewhere in the Pitzer block. In the best case, varying the Eh(V) value and the concentration or reactant quantities I get the following message (the order of magnitude varying slightly) : Ionic strength out of range. Largest residual(s): Resid Resid/Totmol Cbasis -------------------------------------------------------- Cu+ 1.695e+014 1 4.498e-006 -------------------------------------------------------- Finally I found out, that all this trouble only concerns our big data bases (even though working with the D H model). Just starting with thermo_hmw.dat and adding one element (Cu), one redox species (Cu+), some aqueous species and some minerals, the data base works for a saline solution with this one element added and some traces of it as ion. Does anybody know that penomenon ?? Thanks Thomas Willms Finally I found out the reason for the message 'Bad Pitzer Pair'. Now I have the same problem as 'Stephan' : Ion strength out of range. In contrast to him I have a system being much more complicate: # React script, saved Tue Aug 11 2009 by wim data = "D:\Gemeinsame Dokumente\Geochemical-work-bench\Eigenes\DB--Rechnung_geht\_Rechnung1\ZusatzChemapp-Cu\Fe-thermo_hmwZementUran3.dat" verify time start = 0 days, end = 1e6 years temperature = 25 decouple HS- H2O = 20007.8 free kg Na+ = 2577.67 mol K+ = 16.103 mol Mg++ = 94.8337 mol Ca++ = 134.881 mol Cl- = 2604.5501 mol SO4-- = 229.602 mol HCO3- = 4.03732 mol pH = 7.9 swap e- for O2(aq) Eh(V) = -.1 swap Cu+ for Cu++ Cu+ = 1 umolal swap Al(OH)4- for Al+++ Al(OH)4- = 1 umolal swap Fe++ for Fe+++ Fe++ = 1 umolal SiO2(aq) = 1 umolal swap (UO2)2(OH)2++ for UO2++ (UO2)2(OH)2++ = 1 umolal balance on Cl- TDS = 35000 react 1 mol of Cu react 1 mol of Fe slide fugacity of H2(g) 2 react 1 mol of Al react 1 mol of Si react 1 mol of U suppress CO2(aq) Delafossite delxi = 1 linear The calculation works without Uranium, but with Uranium the error depends on the species UO2<2+> <--> U(OH)4 : Program crashes directly : calc_hmw: max charge too large UO2<2+> <--> (UO2)2(OH)2: (see below) Solving for initial system. ...suppressed loading of: CO2(aq) ...suppressed loading of: Delafossite Loaded: 70 aqueous species, 166 minerals, 4 gases, 0 surface species, 14 elements, 7 oxides. Ionic strength out of range. Largest residual(s): Resid Resid/Totmol Cbasis -------------------------------------------------------- (UO2)2(OH)2++ 1.035e+010 1 9e-007 -------------------------------------------------------- this is the same with all other species I have. And concerning the comment of Tom to the post of Stephan: If it is to far from equilibrium, it causes problems... What can I do more than trying all species ? Thanks Thomas Willms Quote Link to comment Share on other sites More sharing options...
Tom Meuzelaar Posted August 12, 2009 Share Posted August 12, 2009 Finally I found out the reason for the message 'Bad Pitzer Pair'. Now I have the same problem as 'Stephan' : Ion strength out of range. In contrast to him I have a system being much more complicate: # React script, saved Tue Aug 11 2009 by wim data = "D:\Gemeinsame Dokumente\Geochemical-work-bench\Eigenes\DB--Rechnung_geht\_Rechnung1\ZusatzChemapp-Cu\Fe-thermo_hmwZementUran3.dat" verify this is the same with all other species I have. And concerning the comment of Tom to the post of Stephan: If it is to far from equilibrium, it causes problems... What can I do more than trying all species ? Thanks Thomas Willms Dear Thomas: I'd be happy to take a quick look at your script- but since you use a proprietary database, I cannot reproduce your problem. Can you email me your database? Send to gwb@rockware.com - I will keep it in confidentiality. Regards, Tom Meuzelaar RockWare, Inc. Quote Link to comment Share on other sites More sharing options...
ThommyW Posted August 13, 2009 Author Share Posted August 13, 2009 Hello , I just remarked that in "thermo-hmw.dat" the alpha2 values of a big number of species is given with zero ? H+ SO4-- beta0 = 0.0298 beta1 = 0.0 beta2 = 0.0 cphi = 0.0438 alpha1 = 2.0 alpha2 = 0.0 K+ Cl- beta0 = 0.04835 beta1 = 0.2122 beta2 = 0.0 cphi = -0.00084 alpha1 = 2.0 alpha2 = 0.0 K+ CO3-- beta0 = 0.1488 beta1 = 1.43 beta2 = 0.0 cphi = -0.0015 alpha1 = 2.0 alpha2 = 0.0 K+ HCO3- beta0 = 0.0296 beta1 = -0.013 beta2 = 0.0 cphi = -0.008 alpha1 = 2.0 alpha2 = 0.0 K+ HSO4- beta0 = -0.0003 beta1 = 0.1735 beta2 = 0.0 cphi = 0.0 alpha1 = 2.0 alpha2 = 0.0 K+ OH- beta0 = 0.1298 beta1 = 0.32 beta2 = 0.0 cphi = 0.0041 alpha1 = 2.0 alpha2 = 0.0 K+ SO4-- beta0 = 0.04995 beta1 = 0.7793 beta2 = 0.0 cphi = 0.0 alpha1 = 2.0 alpha2 = 0.0 where I expect normally 12. Might this a reason for high ionic strength ? Thomas Willms Quote Link to comment Share on other sites More sharing options...
ThommyW Posted November 10, 2009 Author Share Posted November 10, 2009 Hello Tom, I finally foud out that there is one definitive problem with the calculation which results in the error messages "ionic strength out of range" and "charge to large". If I incorporate this spezies in the data base: (UO2)4(OH)7(SO4)4------- * formula= (UO2)4(OH)7(SO4)4 charge= -7 ion size= 4 A mole wt.= 1583.42 g 4 species in reaction 4.0000 UO2++ 7.0000 H2O 4.0000 SO4-- -7.0000 H+ 500.0000 19.0100 500.0000 500.0000 500.0000 500.0000 500.0000 500.0000 as an aqueous species, then any calculation crashes, with or without Pitzer-parameters. Can you check why this happens and where is the problem ? Thanks Thomas Willms Dear Thomas: I'd be happy to take a quick look at your script- but since you use a proprietary database, I cannot reproduce your problem. Can you email me your database? Send to gwb@rockware.com - I will keep it in confidentiality. Regards, Tom Meuzelaar RockWare, Inc. Quote Link to comment Share on other sites More sharing options...
Tom Meuzelaar Posted November 10, 2009 Share Posted November 10, 2009 Hello Tom, I finally foud out that there is one definitive problem with the calculation which results in the error messages "ionic strength out of range" and "charge to large". If I incorporate this spezies in the data base: Hi Thomas: Please email your modified database and React script to me at gwb@rockware.com. Regards, Tom Meuzelaar RockWare, Inc. Quote Link to comment Share on other sites More sharing options...
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